Field of the Invention
The invention relates to an image display device emitting multicolored light, in particular a high-resolution image display device, with a monolithically integrated array.
As substitute for currently used cathode ray tubes for high-resolution colored display of images, image display devices with a monolithically integrated array are currently being developed, which can be produced by production steps used in semiconductor technology. Due to their markedly reduced structural height, the new technology can be provided for entirely new kinds of applications, such as eyeglasses with a built-in color display, or the like. Although LEDs or similar light-emitting individual semiconductor components, which light up in different colors, are already available, nevertheless the production of high-resolution multicolor image display devices presents considerable technical difficulties, among other reasons because LEDs for the three basic colors of red, green and blue cannot be produced using a uniform epitaxial technique. Because of the major differences in material of the individual semiconductor components lighting up in different colors that are required to produce such displays, where the basic materials are GaAsP:N, InGaAlP, and InGaAlN, no solution to the technical difficulties can be expected even in the future. The currently practiced mounting of various finished LED chips on one substrate involves very high costs and is also associated with an only slight attainable resolution.
John van Raalte, in "Matrix TV Displays: Systems and Circuit Problems", published in IEEE Transactions on Consumer Electronics, Vol. CE-21, No. 3, Aug. 1975, pp. 213-219, discloses a plasma image display device emitting multicolored light. There, plasma elements that emit UV light can be combined with photoluminescence phosphors. Television display devices are also known in which LEDs are arranged in the form of a matrix.
Claus Reuber, in "Flachbildschirme . . . der weite Weg zu Nipkows Vision" [Flat Screens--the Long Trail to Nipkow's Vision], published in FERNSEH- UND KINO-TECHNIK [Television and Motion Picture Technology], Vol. 47, No. 4, 1993, pp. 231-242, discloses a television picture reproducing device operating on the principle of the gas discharge technique. In that context it is also known that for full-color reproduction, the neon-argon mixture that lights in an orange red must be replaced with a gas mixture that produces ultraviolet radiation, and the UV must be transformed with luminous substances into the basic colors RGB.
From East German Patent Disclosure DD 0 151 828, it is known to render UV light visible by having the ultraviolet light incite photoluminescence at a suitable point.
German Patent DE 28 20 889 C2 deals with luminescing substances of oxides of alkali metals, rare earths and phosphorus, and their use in cathode ray tubes, as well as devices for converting UV light into visible light.